[GRASS-user] r.walk error: no Starting-Points

[Markus Metz]

On Tue, May 17, 2011 at 10:08 AM, Davd Leif <davd1010 at live.de> wrote:
> Hey,
>
>
> I'm new to GRASS and want to perform an r.walk analysis. I've prepared all
> files grass needs, but I always get the error ERROR: Ausgabe-Rasterkarte
> <ergebniskosten> nicht gefunden (keine Start-Punkte angegeben), means: no
> Starting-Points are given. But I've added starting points via a shapefile.
> Any ideas?
>
Make sure that the current region settings are correct: they must
match the input elevation map
g.region -p rast=myelevation   # -p to print and see if everything is ok

or a subset of the input elevation map
g.region n= s= e= w= align=myelevation -p  # align to grid geometry of
input elevation

Also, the starting points must fall somewhere onto the input elevation
map. You could display the starting points on top of the input
elevation map and zoom to the starting points vector, that should
immediately show you if the starting points fall within the extents of
the input elevation map. The friction map must match the input
elevation map, i.e. must have the same extents and resolution or
represent a subset of the input elevation map's grid geometry.

HTH,

Markus M